Improvement in car-springs



T. F. "ALLEN.-

Car Spring.

Patent ed Nov. 3, 1863.

Witnesses:

Inventor. "i"

use Pnpczfss.)

NITED STATES PATENT OFFICE.

T. F, ALLEN, OFOANANDAIGUA, NEW YORK. IMPROVEMENT IN CAR-SPRINGS.

Specification forming part of Letters Patent No. 40,452. dated November 3, 1863.

To all whom it may concern:

Be it known that I, T. F. ALLEN, of Oanandaigua, in the county of Ontario and State of New York, have invented a new and useful Improvementin Oar-Springs; and I do hereby declare that the following is a full, clear, and exact description of the construction and operation of the same, reference being had to the annexed drawings, makingapart of this specification.

Figure l is a front elevation of my spring, which is represented as not being under pressure. Fig. 2 is a front elevation of the same, represented as being under pressure, and showing a part of the spiral coil closed. Fig. 3 is a vertical section of the same, showing a part of the spiral coils resting upon each other and forming a variable base or hearing for the spring to rest and work upon.

The nature of my invention'consists in the construction of a metallic conical car-spring with spiral coils which have bearingsurfaces and given spaces between them, which close and open gradually under variable degrees of pressure upon the spring, and by means of closing and opening and the variable base or bearing which is thus formed the spring is made to graduate to required pressures upon it, and by the same means the spiral coils are graduated and protected to a great extent against breaking.

To enable others skilled in'the art to make and use my invention, I will proceed to describe its construction and operation.

I coilmy spring upon a mandrel, which is about twice the size or diameter at its large end as is that of its small end. The spiral coils B,Iset a given distance from each othersay about three-sixteenths of an inch-which admits of their being closed and opened as I require of them when they are in operation, and the distance which I allow them to move and then close prevents the setting or straining of the material. It is well known that steel or even iron may be made to deflect a given distance and it will not be overstrained or set, but it will return to its original shape or place. Upon this principle Ihave constructed my spring, and this, together with the varied lengths of its coils, enables me to produce a spring which graduates to the required pressures upon it, and it is not very liable to be broken.

It will be observed that the lengths of ti e spiral coils gradually diminish from the large to the small end of the spring, and that a large spiral coil will close under a less pressure than will-a small one, and it will be further observed that closing and opening the spiral coils produces a variable base or bearing upon which the spring Irests and works, and each spiral coil can move only a given distance, and it will then close and rest upon another, and thus all parts of the spring are protected and graduated, which is not the case with any other spring, (conical, spiral,

or coil,) with which I am acquainted, and I believe I understand the principle upon which other conical, spiral, or coil springs are made and upon which they work.

I am aware that double conical furniture springs have been made, and that they are now in use, and I am also aware that volute springs are in use, and many other kinds of spiral or coil springs; but none of them work as does my spring, nor are such results produced with them as I get with my spring. The spiral spring with rubber interposed between its coils patented by Richard Vose might be improved by making the spring conical or tapering, and I might claim an improvement upon that invention; but it is believed that the principle of my spring is superior to that of any spiral or coil spring now 1n use.

I wish it to be understood that I do not claim a conical or spiral spring in a broad sense.

What I claim as my invention, and desire to secure by Letters Patent, is-

The construction of a metallic conical carspring with spiral coils B, which have bearing-surfaces and given spaces between them,

which close and open, and by means of 0108- ing and opening the spiral coils are protected and the spring is graduated, substantially as described in my specification, and for the purpose set forth.

T. F. ALLEN.

Witnesses: l

W. H. BURRIDGE, HENRY VoTH. 

